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51.
目的探讨胃饲乙醇预处理对肝脏缺血再灌流损伤的影响,并初步评价其预处理的可行性。方法40%乙醇胃饲Wistar大鼠。分组:①大鼠36只,随机分6组:A组8g/kg、B组7g/kg、C组6g/kg、D组5g/kg、E组4g/kg、正常组0g/kg;以中毒症状及肝组织病理为指标,判定大鼠乙醇急性中毒剂量。②大鼠78只,随机分为4组:正常对照组(N)、单纯乙醇组(E)、单纯缺血组(ISCH)、胃饲乙醇预处理组(EPC);采用尾叶转流下的肝缺血模型,于再灌流3、6、12、24h留取标本。结果急性胃饲乙醇≤5g/kg预处理后,动物中毒症状轻,无死亡;乙醇预处理可以在一定程度上减轻肝脏90min的缺血再灌流损伤。结论适当剂量的乙醇胃饲预处理是一种安全的预处理措施,有望成为增强肝脏对缺血再灌流损伤耐受性的一种较好的预处理方式。  相似文献   
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Audiogenic seizures can be induced in DBA/2J mice following intense auditory stimulation. A number of neurotransmitters, including 5-hydroxytryptamine (5-HT), are believed to be involved in mediating this effect since it has been shown previously that depletion of 5-HT or blockade of 5-HT receptors protects DBA/2J mice from these audiogenic seizures. The present study was undertaken to determine whether antagonism of the newly identified 5-HT7 receptor may protect DBA/2J mice from audiogenic seizures by attempting to correlate in vivo potency of compounds with their affinity at the 5-HT7 receptor. All compounds used in the correlation were shown to be antagonists at the 5-HT7 receptor and a statistically significant correlation was observed between 5-HT7 affinity and doses for half-maximal response (ED50) for protection of DBA/2J mice from sound-induced seizures (r = 0.80; P < 0.05). No significant correlation was observed between in vivo activity and affinity at either 5-HT1A, 5-HT2A or 5-HT2C receptors. It is also unlikely that interactions between the 5-ht5 receptor will protect DBA/2J mice from audiogenic seizures since metergoline and mesulergine which are both active in this in vivo model have no affinity for the 5-ht5 receptor. There are similarities between the pharmacology of the 5-HT7 receptor and that of the 5-HT1A receptor, however the correlation between the in vivo potency in DBA/2J mice and 5-HT1A affinity was not significant. Furthermore, the 5-HT1A receptor antagonist WAY 100135 did not protect DBA/2J mice from audiogenic seizures at doses that antagonise 5-HT1A receptor-mediated effects in mice. These data suggest that antagonism of 5-HT7 receptors may protect against audiogenic seizures in DBA/2J mice although a definitive conclusion must await studies with selective 5-HT7 antagonists. Received: 20 March 1997 / Accepted: 10 August 1997  相似文献   
54.
目的:比较二维超声心动图(2DE)和心电图(ECG)对心肌梗塞(MI)定位诊断的异同、优劣。方法:对59例 MI 患者进行了2DE 和 ECG 检查。在2DE 上将左室分为16个节段而分别确定与 ECG 各导联的对应关系,分别计数2DE 上室壁运动异常(WMA)节段数和 ECG 上有异常 Q 波导联所对应节段数,对比分析两种方法检查结果的一致性。结果:2DE 和 ECG 分别检出338和311个节段阳性,两种方法阳性一致率57.9%,两种方法阳性一致率在各壁的高低依次为下壁、前壁、后壁、前间隔、侧壁;两种方法检测结果的差别有显著性(P<0.05);两种方法检测结果的相关系数 r=0.595(P=0.0000)。结论:两种方法的检查结果有较好的一致性,2DE 优于 ECG。  相似文献   
55.
Abstract  Although respiration in trained canines is well investigated, the process of preparing dogs has not been described in any great detail. Moreover, their daytime patterns of sleep and wakefulness during 1 or 2 h of electroencephalogram (EEG) and electrocardiogram (ECG) recordings are not clear. Therefore, we describe the process of selecting and training dogs, in which we recorded EEG and ECG in the laboratory. First, 14 of 1242 dogs dealt with over a 1 year period were chosen. They were trained for 2 h to lie quietly and to sleep in the laboratory; this training procedure was repeated 152 times. Three dogs were then selected and a permanent tracheostomy was performed in one. Finally, EEG and ECG were recorded with the bipolar fine needle electrodes; respiration was recorded simultaneously through a tube inserted to a tracheostomy in one dog. Wakefulness, slow wave sleep (SWS) and rapid eye movement (REM) sleep (REMS) were identified according to the EEG pattern and on the basis of the behavioral criteria. Recordings were performed 12 or 13 times in each dog. Complete sleep cycles, including wakefulness, SWS and REMS in this sequence, were observed 3.9–4.1 times. The mean duration of SWS was 2.2–4.4 min and that of REMS was 3.5–4.6 min. The REMS latency was 33.9–41.8 min. Fluctuation of heart rate with respiration, termed respiratory sinus arrhythmia, was noted in the ECG. Heart beat increased with inspiration and decreased with expiration. The present study demonstrates how to select and train sleeping dogs and shows their undisturbed daytime sleep and wakefulness patterns.  相似文献   
56.
本文报道1988年6月~11月,单独应用上海交通大学电力工程系研制的JT—ESWL—Ⅱ型体外震波碎石机,治疗尿路结石506例,其中肾结石304例(双侧12例)输尿管结石199例(双侧5例),膀胱结石3例。冲击能量15~40焦耳,每次治疗冲击波次数为400~2800次。本组无开放手术、无肾脏丧失、无死亡。效果满意者96.44%。其并发症主要有血尿、结石串。作者认为单用ESWL治疗小于3Cm的尿路结石安全可靠、无严重并发症。文中对单用体外震波碎石(ESWL)治疗尿路结石病例选择,如何减少并发症,提高治疗效果进行了讨论。  相似文献   
57.
The pharmacokinetics and haemodynamic effects of isosorbide dinitrate (ISDN) have been investigated following administration of single doses as a sublingual (SL) spray (2.5 mg), sublingual tablet (5 mg) and peroral tablet (10 mg) in a randomised, placebo-controlled double-blind cross-over trial in 16 healthy volunteers.After the sublingual spray Cmax was higher (39.0 ng·ml-1) and tmax was shorter (3.9 min) than after the sublingual (22.8 ng·ml-1 and 13.8 min) and peroral (16.9 ng·ml-1 and 25.6 min) tablets. The AUC of ISDN did not differ following any of the three formulations (1031; 879; 997 ng·ml-1·min, for the spray, SL tablet and PO-tablet, respectively). Mononitrate metabolites of ISDN (IS-2-MN and IS-5-MN) and total nitrates in plasma increased in proportion to the administered dose. This indicates that the fraction of the dose absorbed was the same for all the formulations but that the extent of first-pass metabolism increased in the order sublingual spray < sublingual tablet < peroral tablet. Thus, compared to the spray, the relative bioavailability of ISDN was 48% and 28% from the sublingual and peroral tablets, respectively.The haemodynamic effects were quantified using the a/b ratio of the finger pulse wave and the systolic blood pressure and heart rate under orthostatic conditions. For the a/b ratio of the finger pulse, the maximal effect was higher (emax=130%) and the time to emax (temax) shorter (16.6 min) after the spray than the sublingual tablet (84.4% and 25.5 min) or peroral tablet (90.2 and 31.3 min). The onset of effect was within 3, 5 and 7.5 min after the spray, sublingual and peroral tablets, respectively. A larger change in the orthostatically-induced decrease in systolic blood pressure and increase in heart rate was obtained following peroral than sublingual administration despite the similar plasma concentrations of ISDN. This probably reflects the larger amount of pharmacodynamically active mononitrate metabolites formed after oral dosing. The integrated effect following administration of 2.5 mg ISDN as spray was similar to that of a sublingual tablet of 5 mg.  相似文献   
58.
彩色多普勒在心脏起搏器综合征诊断中的应用价值   总被引:1,自引:1,他引:0  
目的 :探讨运用彩色多普勒血流显像 (CDFI)并结合心电图 (ECG)诊断起搏器综合征 (PMS)的临床价值。方法 :对具有详实临床及ECG资料的心室按需 (VVI)起搏器安置患者 6 0例及对照组 4 8例进行CDEI检查 ,观察起搏组与对照组的三尖瓣返流 (TR)的发生率、返流程度 ,并分析二者之间的相关性。结果 :起搏组出现逆传P波 (即PMS阳性 )者 15例 ,CDFI检测出现TR者 2 0例 ,明显高于对照组 ,且PMS阳性者TR发生率明显高于PMS阴性者 ,表明安置VVI起搏器后出现逆传P波与TR的发生相关性良好。结论 :CDFI对PMS的诊断具有重要意义 ,尤其将ECG与CDFI结合应用有助于诊断率的提高。  相似文献   
59.
对18只大鼠进行内皮素脊髓鞘内注射,观察及记录大鼠后肢功能状态,并将18只大鼠分为3个不同的时间处死,进行病理形态学观察。结果表明:3组均表现缺血缺氧病理改变。2及4h实验组病变重于30min实验组。脊髓下胸段、腰段病变重于颈段及骶尾段。同时发现,大鼠后肢的功能状态与其脊髓相应的病理形态学变化不呈正比。  相似文献   
60.
中西医结合治疗缺血性脑血管病临床疗效观察   总被引:1,自引:0,他引:1  
目的 回顾性分析中西医结合治疗缺血性脑血管病的疗效。方法 对126例缺血性脑血管病患者,在早期西医溶栓、抗凝、降低血液粘度、扩张血管和促进脑细胞代谢等治疗基础上,结合中医辩证施治治疗。结果 42例瘫肢肌力恢复达V级;48例肌力≥Ⅳ级,言语流畅;27例生活能基本自理,可依杖散步,肌力≥Ⅲ级:9例与治疗前对比肌力提高Ⅰ~Ⅱ级,但生活仍不能自理。结论 在西药治疗基础上,结合益气活血中药调理可显著提高患者的疗效。  相似文献   
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